Adjustable control for automatic vacuum cleaners



Aug. 14, 1956 F. c. DOUGHMAN Er AL ADJUSTABLE CONTROL FOR AUTOMATIC VACUUM CLEANERS 5 Sheets-Sheet 1 Filed Jan. 29, 1.954

Aug. 14, 1956 F. c. DOUGHMAN ET AL 2,758,670

ADJUSTABLE CONTROL FOR AUTOMATIC VACUUM CLEANERS 5 shee'ts-sneet 2 Fivled Jan. 29, 1954.

INVENTORS y. ATTORNEY F. c. DOUGHMAN ET AL ADJUSTABLE CONTROL FOR AUTOMATIC VACUM CLEANERS Filed Jan. 29, 1954 5 Sheets-Sheet 3 ATTORNEY Aug. 14, 1956 F. c. DoUGHMAN ET AL 2,758,570

ADJUSTABLE CONTROL FOR AUTOMATIC VACUUM CLEANERS 5 Sheets-Sheet 4 Filed Jan. 29, 1954 ATToNEY ug- 14 1956 F. c. DOUGHMAN ET AL 2,758,670

ADJUSTABLE CONTROL. FOR AUTOMATIC VACUUM CLEANERS Filedl Jan. 29, 1954 5 Sheets-Sheet 5 [l Y I l ATTORNEY United States Patent() ADJUSTABLE CONTROL FOR AUTOMATIC VACUUM CLEANERS Ferman C. Doughman, Darien, John Kosik, Jr., Byram, and John T. Ferraris, Stamford, Conn., assignors to Electrolux Corporation, Old Greenwich, Conn., a corporation of Delaware Application January 29, 1954, Serial No. 407,096

Claims. (Cl. 18S-37) Our invention relates to vacuum cleaners and more particularly to vacuum cleaners of the automatic type wherein the operation of the cleaner is controlled in accordance with variations in air pressure occurring within the cleaner during use.

A preferred arrangement involves a pressure differential diaphragm or the like which is responsive to the pressure drop of the air passing through the dust bag or other dust separating member for actuating a valve controlling the application of pressure or vacuum to a power diaphragm. Such device is so designed and constructed that it will actuate the valve upon the attainment of a predetermined pressure drop. The resulting actuation of the power diaphragm may cause merely the operation of a visible or audible signal, or it may include stopping the motor of the cleaner, opening the front cover and ejecting the dust container, or any one or more of these operations.

However, the value of the pressure drop at which it is desirable to have the control responsive may vary under different conditions. For example, if the dirt being picked up is relatively ne, it will quickly clog the pores 'of the dust bag with the result that a predetermined pressure drop of the air passing therethrough will result from a comparatively small quantity of this dirt. Anincrease in the pressure drop through the bag results in a decrease in the suction available at the nozzle and `it is for this reason that it is desirable to stop the operation of the cleaner, or at least give warning to the operator, when the nozzle suction has reached such a low value that continued operation would be inefficient in that the nozzle would not pick up suicient dirt. However, if the dirt being picked up is of the aforesaid fine character, less suction at the nozzle is required to remove it and therefore a greater pressure drop through the bag is permissible before the cleaning becomes ineilicient. l

Also, variations in the voltage of the` electric current supplied to the motor of the cleaner changes the speed of the motor and of the fan driven thereby, and this results in changes in the suction produced by the fan which in turn varies the pressure drop through the dust bag without correspondingly altering the suction at the nozzle.v Thus, an increase in voltage above normal increases the pressure drop through the bag but also increases the su.`v tion at the nozzle, whereas an increase in pressurey drop due to a greater accumulation of dirt would decrease the' nozzle suction. Hence, under conditions of high voltage a greater pressure drop is permissible as satisfactory cleaning eciency will still be maintained.

Consequently, the prime object of our invention is to provide a control which may be readily adjusted from the exterior of the cleaner so as to vary the pressure drop through the dust bag at which the control will operate.

In accordance with our present invention, the aforementioned pressure difterential diaphragm is designed and constructed so as to effect the desired control uponthe attainment of a predetermined pressurediterential acting on opposite sides of the diaphragm. However,

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means are provided for bleeding air at an adjustable rate into or out of the chamber on one side of the diaphragm so that the pressure differential acting on the diaphragm is not the same as the pressure drop through the dust bag. Thus, if atmospheric air is bled into the diaphragm chamber which is connected to the region of high vacuum between the bag and the inlet of the fan, a greater pressure drop through the bag and hence a higher vacuum in this region is required in order to actuate the diierential diaphragm, than would be the case if no atmospheric air were bled in. Consequently, by adjusting the rate at which atmospheric air is bled, it is possible to vary the pressure drop through the bag which is required to cause the differential pressure diaphragm to actuate the controls. A similar effect may be produced by bleeding air out of the diaphragm chamber which is connected to the region of lower vacuum ahead of the bag, such air being bled into the region of higher vacuum, while an opposite e'ect may be obtained by bleeding atmospheric air into the last-mentioned chamber.

Further objects and advantages of our invention will be apparent from the following description when considered in connection with the accompanying drawings which form a part of the specification and of which:

Fig. 1 is a side view, chiey in cross-section, showing a vacuum cleaner embodying our invention;

Fig. 2 is a top view on an enlarged scale of a control unit and front cover of the vacuum cleaner shown in Fig. l;

Fig. 3 is a cross-sectional view on an enlarged lscale taken on the line 33 of Fig. 2;

Fig. 4 is a cross-sectional view on an enlarged scale taken on the line 4-4 of Fig. 2;

Fig. 5 is a cross-sectional View taken on the line 5 5 of Fig. 2;

Fig. 6 is a cross-sectional view similar to Fig. 5, but showing another embodiment of our invention;

Fig. 7 is a cross-sectional view like Fig. 6, but showing a further embodiment of our invention;

Fig. 8 is a view, chiey in cross-section of an embodiment -of our invention including an improved form of valve;

Fig. 9 is a cross-sectional view taken on the line 9-9 of Fig. 8;

Fig. l0 is a bottom view looking in the direction of the arrows 10-10 in Fig. 9;

Fig. 11 is a view, partially in cross-section of another embodiment of an improved valve;

Fig. 12 is a view similar to Fig. 11, but showing a still further form of valve;

Fig. 13 is a cross-sectional view of still another form of valve;

Fig. 14 is a cross-sectional View taken on the line 14-14 of Fig. 13, but with some of the parts shown in elevation; and

Fig. l5 is a bottom View looking in the direction of the arrows 15-15 of Fig. 14.

Referring to the drawings, and more particularly to Fig. 1, reference character 10 designates an airtight elongated body mounted on a pair of runners 12 which movably support the body in a substantially horizontal position on a surface, such as a floor. Disposed yon the righthand portion of the body, as viewed in Fig. l, is a motorfan unit comprising a fan 14 driven by an electric motor 16, the motor-fan unit being mounted within the body by means of an airtight partition or bulkhead 18. The fan is provided with an inlet opening 20 which communicates with the space wi-thin the body to the left of the bulkhead. Within `this space there is disposed an inner body 22 formed with a large number of apertures 2,4 so as to provide substantially unobstructed communication benl? tween the interior of the inner body and the inlet 20. The left end of the inner body is open and is secured to a ring 26 which is in turn secured in the open end of the outer body 16.

Depending from the lower part of ring 26 is a wall portion 28 which forms the front end and part of the bottom of a control chamber 311. The enclosure of the chamber 30 is completed by a removable stamping or the like 31. Extending forwardly from the wall 28 is a pair of projections 32 to which is hinged a cover 34 by means of a pin 36. A coil spring 38 surrounds this pin and urges the cover to the open position shown in Fig. 2. As seen in Fig. 2, the left-hand portion of the cover, which is the upper portion when the cover is closed, is formed with a cut-out portion 40 within which is pivotally mounted a hose connector member 42 by means of pins 44. A link 48 is pivotally connected to the hose connector and to one of the projections 32, this link together with the cover 34 constituting a parallel motion linkage for causing the hose connector 42 to move parallel to itself as the cover is opened and closed.

The hose connector is formed with an opening 50 extending therethrough, the outer end of which is formed as a portion of a separable coupling whereby a suction hose may be connected thereto. The inner end of the opening communicates with an inlet conduit 52 which is surrounded by a i'lexible gasket 54.

Removably disposed within the inner body 22 is a dust separating member 56 made of porous material, such as paper, which is secured at one end to a stii cardboard disc 58. This disc is formed with a centrally located aperture adapted to receive the inlet conduit 52 when the cover is in the closed position shown in Fig. 1, the gasket 54 bearing against the disc and holding the edges thereof in position against a gasket 66 carried by the ring 26, thus closing this end of the body 10.

Secured below the airtight body 1t) by means of a plurality of bolts 62 is a control unit comprising a differential pressure diaphragm housing 64 and a power diaphragm housing 66. Secured within the housing 64 is a differential pressure diaphragm 68 which divides the housing into an upper high vacuum chamber 7@ and into a lower low vacuum chamber 72. Chamber 70 is connected to the interior of body through an opening '/'4 in the housing which communicates with an aperture 76 in the body. A gasket 77 is carried by housing 64 and bears against the bottom of body 1t) around the opening 76 to prevent leakage. This chamber 70 may also be connected to atmosphere through an adjustable valve 78. This valve includes a screw threaded valve member 80, the end of which may be adjustably positioned with respect to a passage 82 leading to the chamber 78. The outer end of the valve member is provided with a knurled knob or the like 84 which extends through an opening 85 in stamping 31 in order that it may be manually adjusted from the exterior of the cleaner. A packing ring 86 is preferably provided in order to offer sufficient re sistance to turning so that the valve member will not be accidentally moved as a result of vibrations.

A flexible conduit 88 is connected to the lower chamber 72 and leads to a passage 90 formed in the hose connectorV 42 and communicating with the passage 511 therein. Thus it will be seen that the lower surface of the diaphragm 68 is subjected to the pressure existing within the passage 50, which is the pressure ahead of the bag S6, while the upper surface of the diaphragm is `subjected to the pressure existing within the body 10 between -the bag and the fan, except as this pressure may be modied by atmospheric air bled in through the valve 78.

A spring 92 is disposed between the upper surface of diaphragm 68 and the upper wall of housing 64. This wall is formed with a valve port 94 which is controlled by means of a valve 96 which is urged towards closed position by a loading spring 98. The valve is provided with a stem 100 which, in the position shown in Fig. 5, is disposed some distance above the diaphragm 68.

A passage 192 connects valve port 94 with a chamber 104 in housing 66 above a power diaphragm 166. This diaphragm is urged downwardly by a coil spring 108 and carries a stem 110. Secured to the upper end of the stem is a valve member 112 which controls iow through a port 113 leading from the chamber 184 to the interior of the body 10. A gasket 114 is carried by the housing 66 and bears against the bottom of body 10. The space below the diaphragm 106 is open to the atmosphere through one or more openings 115.

Secured within the body 1@ adjacent to the port 113 is a bracket 116 on which is pivotally mounted a rocker arm 118 one end of which is disposed above the stem 111i of the power diaphragm. The other end of the arm bears against a pin 120 slidably mounted in the bracket 116, and the lower end of the pin bears against the inner end of a front cover latch 122 which is pivotally mounted on the wall 28 at 124. The outer end of this arm is formed with a shoulder 128 which is adapted to engage a keeper 130 mounted on the front cover 34 so as to retain the cover in closed position. A spring 132 urges the latch arm 122 towards the position shown in full lines in Fig. 4.

Arm 118 is secured to a pin 134 on which it is pivotally mounted and this pin extends to one side of the bracket 116, where it is provided with a cam 136. This cam bears against a leaf spring 138 secured to the bottom Wall of housing 1G and carries at its free end a stop 140.

The bottom wall of inner body 22 is formed with an'elongated slot 142 in which is disposed a cylindrical rail 144, the front end of which is secured to the ring 26, while the rear end is secured to the rear wall of the Vinner body. Slidably mounted on the rail 144 is an ejector member 146. A normally at leaf spring 148 is disposed between the rear wall of the inner body and the ejector member and tends to move the latter towards the left, as viewed in Fig. l. Slidably mounted below the rail 144 is a latch bar 150 near the rear end of which is secured a leaf spring 152. Ejector 146 is formed with a lip 154 which, in the position of the parts shown in Fig. 1, is engaged by the spring 152. The front end of the latch bar 151B abuts against the stop so as to retain the ejector 146 in its rearward position with the spring 148 compressed. A bracket 156 carried by the rear wall of the inner body is formed witha lower inclined surface 158 so arranged with respect to the spring 152 that movement of the latch bar 15.0 to the left causes the inclined surface to cam the free end of the spring 152 downwardly and out of engagement with the lip 154 of the ejector, thus releasing the latter for movement by its spring 148.

An electric switch 166 is provided for controlling the supply of current to the motor 16, This switch may be manually actuated by means of a pivoted member 162. In the position shown in Fig. l, the switch is off and pivoting of the member 162 in a clockwise direction serves to close the switch. Slidably mounted adjacent the switch isa bar 164 which is urged towards the left, as viewed in Fig. 1, by means of a spring 166. This bar is provided with a projection 168 which is contacted by the front cover when the latter is closed so as to hold the bar in the position shown. This bar is provided with an upstanding arm 170 which is positioned so as to strike a pin 172, extending outwardly from the switch actuating member 162, when the latter is in the on position. Thus, if the switch is on and the front cover is opened, the bar 164 moves to the left under the inuence of its spring 166 and arm 170 contacts pin 172 so as to automatically throw the switch to the off position.

The above described device operates as follows:

With parts in the position shown in Fig. l, that is with a clean dust bag in place within the body and the front Cover closed, operation of the motor-fan unit serves to draw air in through the inlet 52. This air passes with but little resistance through the porous material of the bag and through the many openings 24 of the inner body to the inlet of the fan. The pressure existing within the inlet is communicated through the conduit 88 to the chamber 72 below the pressure differential diaphragm 68. The pressure existing within the inner body between the bag and the inlet of the fan is communicated to the chamber above the diaphragm through the opening 76 and the passage 74. Assuming that the valve 80 is closed, the diaphragm 68 consequently is subjected to the differential of these two pressures, which corresponds to the pressure drop through the dust bag. When the bag is clean there is but little pressure drop through it and consequently this differential is very small and is not suicient to displace the diaphragm upwardly against the force of the spring 92. However, if dirt is introduced into the bag with the incoming air, it is retained within the bag and gradually clogs the pores thereof so as to increase the pressure drop. This of course increases the differential acting on the diaphragm 68 and starts to raise the latter by compressing the spring 92. The more this spring is compressed the greater is the resistance which it olfers to further compression and the spring is so selected with respect to the area of diaphragm 68 that the diaphragm will contact the valve stem when the pressure drop through the bag has attained a value such that continued operation of the cleaner would be inetiicient.

When the diaphragm contacts the stern 100 it lifts the valve 96 so as to establish communication through passage 102 between the high vacuum chamber 70 and the chamber 104 above the large power diaphragm 106. This causes the latter to start moving upwardly against the force of its spring 108, which movement opens the valve 112, thus establishing direct communication through the large port 113 between the chamber 104 and the interior of the body 10, which causes the diaphragm to quickly move to its upper limit. When the valve 96 opens, air is exhausted from chamber 104 through passage 102 into chamber 70 and hence there is a slight decrease in the vacuum in the latter chamber which tends to lower the diaphragm 68 and close the valve 96. Also, the pressure drop through the bag fluctuates with changes in air flow, and if the air flow were reduced, as by placing the nozzle on a surface which seals its opening more tightly, just after valve 96 had opened, the resulting reduction in pressure drop might be enough to close the valve. However, even if the valve 96 is thus closed, this will not interfere with the actuation of the power diaphragm 106, inasmuch as initial displacement thereof opens valve 112, and hence high vacuum is thereafter applied directly to the power diaphragm independently of whether or not valve 96 remains open.

Upward movement of the power diaphragm causes its stem to pivot the arm 118 in a counterclockwise direction, as viewed in Fig. 4. This depresses the pin which in turn pivots the latch 122 in clockwise direction so as to disengage it from the keeper of the front cover. The spring 38 thereupon opens the cover and when this occurs the projection 168 on the bar 164 is released and the spring 166 moves the bar to the left, as seen in Fig. 1, thus moving the switch member 162 to its off position, which stops the operation of the motor-fan unit.

Pivoting of the arm 118 causes pin 134 to turn in a counterclockwise direction, as viewed in Fig. 3, thus causing cam 136 to depress the spring 138, which withdraws the stop 140 from contact with the left end of the ejector latch bar 150. As the right-hand end of this bar is coupled to the ejector through engagement of the leaf spring 152 with the lip 154, the ejector spring 148 moves both the ejector and the bar 150 to the left. The inclined surface 158 on the bracket 156 I thereupon cams the spring 152 downwardly and out of engagement with the lip 154, whereupon the ejector is moved all the way to the left, pushing the bag ahead ot' it and out of the cleaner.

With the valve 80 fully closed, as was assumed in the above description, the pressure existing in the chamber 70 is the same as that existing within the body 10 and consequently the pressure differential acting on the diaphragm 68 is equal to the pressure drop through the bag. However, if the valve 80 is open so as to bleed atmospheric air into the chamber 70, the vacuum existing in this chamber will be less than that existing within the body 10 and hence the pressure differential acting on the diaphragm will be less than the pressure drop through the bag. Consequently, a greater pressure drop through the bag will be required in order to establish the pressure dierential necessary to cause the diaphragm 68 to open the valve 96, and the more the valve 80 is open the greater will be the pressure drop through the bag required to act'uate the automatic controls.

In the embodiment illustrated in Fig. 6 the chamber 72 below the diaphragm 68 is connected through the needle valve 174 with the chamber 70 above the diaphragm, which is in open communication with the in-` terior of the body 10 through the passage 74 and the opening 76. With the valve 174 closed the device operates in the same manner as does the embodiment previously described when the valve 78 is closed. However,

opening of the valve 174 will increase the vacuum exist-L ing within the chamber 72, inasmuch as there is always a higher vacuum in the body 10 than there is in the inlet passage ahead of the bag. Thus, opening of the valve 174 will reduce the pressure differential acting on the diaphragm 68 by increasing the vacuum acting on the lower side of the diaphragm. This produces the same result as decreasing the vacuum acting on the upper side of the diaphragm by opening the valve 78 in the previous embodiment.

In the embodiment illustrated in Fig. 7 the chamber 72 below the differential pressure diaphragm 68 is connected through the needle valve 176 with the atmosphere. With the valve 176 closed the device operates in the same manner as do the two previously described embodiments when the respective valves 78 and 174 are closed. However, opening of the valve 176 will decrease the vacuum existing within the chamber 72 by the bleeding of atmospheric air thereinto. Consequently, opening of the valve 176 will increase the pressure diierential acting on the diaphragm 68 by decreasing the vacuum acting on the lower side ot the diaphragm. This produces the opposite result from that produced by either decreasing the vacuum above the diaphragm in the first embodiment or increasing the vacuum below the diaphragm in the second embodiment, Hence, opening the valve 176 will decrease the pressure drop through the dust bag which is required to cause the diaphragm 68 to open the valve 96 and thus actuate the controls.

In the embodiments described above, the regulation of the bleeding of air int'o the diaphragm chambers has been accomplished by means of a more or less standard type of valve, such as the needle valve shown in either Fig. 6 or Fig. 7 or the valve 78 shown in Fig. 5. In these valves variations of flow is obtained by varying the size of the orifice through the valve by moving a valve member towards or away from a fixed seat. While such a valve will of course regulate the ow therethrough, we have found that particularly within a certain range of movement, a very slight movement of the valve member results in a comparatively large change in the rate of flow. inasmuch as the total quantity of air tiowing through the valve is slight, it is difficult for-a relatively unskilled Iperson to properly adjust the valve because within one range of movement a slight change in the position of the valve member may produce a much larger change in the setting 7 of the control unit than would be produced by the same change in position within another range.

In the different forms of valves disclosed in Figs. 8 through 15, the valve comprises two relatively movable members, one -of which is formed with a single orifice of iixed size, while the other is provided with a plurality of fixed orifices of graduated sizes so arranged that any one of the graduated orices in the latter member may be aligned selectively with the single orifice in the former member. This gives what might be termed a step-bystep control which is much more easily adjusted than is the continuous control of the previously described embodiments. The sizes of the graduated orifices may be so selected that the same amount of change in the setfing of the control unit is produced by each step in the adjustment of the valve.

In Fig. 8 the valve is shown in conjunction with a control unit which differs somewhat from that shown in Fig. 5. In this embodiment the lower part of the diaphragm chamber 64 is formed by a cylindrical flange 180 extending upwardly from a member 182 which serves as a bottom wall or closure for the control chamber 38, thus replacing the member 31 shown in the preceding gures. The stern 100 of valve 96 is slidably carried in a spider 184 which is provided with perforations 186. The valve 96 carries a ange 188 disposed above a diaphragm 190 which is located in a diaphragm chamber 192 to which is connected the conduit 1112 leading to the power diaphragm. The space below the diaphragm 198 is open to the atmosphere through one or more ports 194.

The chamber 70 above the differential pressure diaphragm 68 is connected by means of a conduit 196 with a valve designated generally by reference character 198. This valve includes a cylindrical member 288 which is open at both ends and is formed with a bracket 202 at its lower end which is secured by means of rivets or the like 204 to the member 182. The upper end of the cylinder 200 is permanently closed by means of a cap 206 and the conduit 196 communicates with the space within the member 200 between the cap 206 and an intermediate wall 208. This wall is formed with a plurality of apertures 210 of graduated sizes. As shown in Fig. 10 there are tive of these apertures arranged in a circle around the axis of the cylindrical member 200 and disposed equidistant from each other, except that there is a double space between the largest and the smallest aperture. Disposed within the member 208 below the wall 208 is a rotatable valve member 212 formed with a single aperture 214 which is larger than any of the apertures 210. This member is preferably made of compressed carbon so as to make sealing contact with the lower surface of wall 208 and with the inner cylindrical surface of member 200. Member 212 is formed with one or more projections 216 which extend into corresponding recesses formed in the end of a hollow knob 218 which is rotatably received within member 284) and extends through an opening 219 in member 182 so as to be accessible for manipulation. A coil spring 220 is disposed between knob 218 and member 212 so as to urge the latter into contact with wall 288. Member 218 is retained in place within the member 200 by means of spring clip 222 which extends through diametrically opposed slits 224 in the member 20() and engages an annular groove formed in the Out'er surface of member 218.

The lower surface of bracket 202 is provided with a plurality of detents 226 equal in number to the number of orifices 210 plus one. Knob 218 is formed with a radially projecting extension 228 formed with an aperture therein which is adapted to receive any one of the detents 226. The detents are so located with respect to the apertures 210 and the projection 228 is so located with respect to the aperture 214 that whenever one of the detents is located within the opening formed in the projection 228, the orifice 214 is in alignment with one of the orces 210, or with the blank space between the largest and smallest aperture, which latter position represents complete closure of the valve.

This embodiment operates in a manner similar to that shown in Fig. 5. With the valve adjusted so that the oriiice 214 is in alignment with the blank space in the wall 288, the differential pressure acting on the diaphragm 68 is equal to the pressure drop through the dust bag. As this increases, the diaphragm 68 is moved upwardly against the force of its loading spring 92 until it contacts valve stem 108. Further upward movement of the diaphragm, caused by a further increase in pressure drop through the dust bag, lifts the valve 96 against the force of its spring 98, thus connecting diaphragm chamber 192 above the diaphragm 190 with diaphragm chamber 70. Consequently, a high vacuum is produced in the chamber 192, causing the diaphragm 190 to lift up against the disc 188 of t-he valve 96 so as to fully open this valve and maintain it open even though the pressure differential acting on the diaphragm 68 should be decreased. Opening of the valve 96 also produces a high vacuum on the power diaphragm through the conduit 102.

If it is desired to increase the pressure drop through the bag which is required to effect an opening of the valve 96, the valve 198 is adjusted by turning the knob 218 so as to align the orifice 214 with a selected one of the graduated orices 218. This permits atmospheric air to be bled into the diaphragm chamber 7i) through the conduit 196, which produces the same result as the bleeding of air through the valve '78 in Fig. 5. The engagement of the detents 226 in the aperture formed in projection 228 informs the operator when the orifices of the valve are properly aligned and assures that the valve will not be moved out of adjustment by vibration or the like.

In the embodiment illustrated in Fig. ll the conduit 196 leading from diaphragm chamber 70 is formed with a hemispherical end. Rotatably mounted on a pin 230 carried by member 182 is a circular disc 232 made of nylon or some suitable flexible material. The face of this disc is formed with a plurality of hemispherical recesses 234 arranged in a circle around the center of the disc. From each recess an oriiice 236 extends through the disc and these orifices are graduated in size, in the same manner as the orifices 210 in Figs. 9 and l0. The edge of the disc 232 extends through an opening 238 in member 132 and this edge is preferably serrated.

In order to vary the rate of flow of air bled into the diaphragm chamber 7i), the disc 232 is rotated so as to bring the conduit 196 into alignment with different sized orices. The spherical end of the conduit enters recesses 234 in disc 232 so as to properly align the orices in the latter with that in the end of the conduit and to retain the valve in adjusted position. The resiliency of the disc 232 permits it to be deformed slightly so as to allow it to be turned from one position to the next.

In the embodiment illustrated in Fig. 12 the end of the conduit 196 is` provided with a hollow cup-shaped member 240 made of rubber or other suitable resilient material which bears against the face of a disc 242, which is similar to the disc 232, except it need not be made of resilient material. This disc is formed with a plurality of openings 236 of graduated sizes and is rotatably mounted on a pin 239. The edge of the disc extends through a slot 238 formed in member 182 so as to be accessible for rotation. A spring 244 is mounted on the member 182 and is adapted to cooperate with recesses 246 in the anged skirt of disc 242 so as to properly locate the oriiices 236 with respect to the cup 240. The resilient nature of the latter provides a seal with the face of the disc so that all of the air passing through the conduit 196 must pass through the aligned orifice of the disc 236.

' The valve shown in Figs. 13 through l5 is similar to that shown in Fig. 12, in that it employs a cup 240 of exible material cooperating with the face of a disc 248 in which is formed a series of orifices 236 of graduated sizes. However, the disc 248 is mounted on a pin 250 which is rotatably carried within a sleeve 252 secured to member 182, and the pin is also axially displaceable within the sleeve, a coil spring 254 being provided for urging the pin upwardly so as to hold the disc in contact with the cup 240. A knob 256 is secured-to the outer end of the pin and is disposed on the exterior of member 182. The inner end of this knob is provided with a plurality of recesses 258 which receive a xed pin 260. With the parts in the position shown in Fig. 13, that is with the pin 260 within one of the recesses 258, rotation of the knob 256 is prevented. In order to rotate the knob, it is necessary to rst pull it outwardly to free the recess from engagement with the pin. This also moves the disc 248 out of contact with the cup 240. In this axially displaced position, the knob and disc may be rotated so as to align a diierent size orice 236 with the cup 240. During rotation of the disc no Wear is imposed on the cup and there is no tendency for the ilexible edges of the cup to be pulled out of shape or otherwise damaged. The operation of this form of valve is the same as that shown in Fig. l2. If desired, a dial 262 may be secured to the outside of member 182 and suitably calibrated as is shown in Fig. l5. As there shown an arrow 264 on knob 256 points to the number 6 on the dial, which indicates that the valve lis in its fully opened position, that is with the largest orice 236 in alignment with the cup 240, whereby a maximum amount of atmospheric air is bled into the diaphragm chamber 70, which in turn requires a maximum pressure drop through the bag to eiect the displacement of the diaphragm 68 which is necessary to open the valve 96. Preferably, the knob 256 is formed with a projection 266 between the recesses 258 corresponding to positions l and 6, which projection is higher than those between any of the other recesses. rDhis prevents the knob from being turned directly from position l to position 6 and viceversa, and informs the operator when the valve has been turned to either of its extreme positions, even though he is not looking at the calibrated dial.

It will thus be seen that in any of the embodiments the automatic controls of the cleaner may be readily adjusted in accordance with particular conditions existing in the home where the cleaner is being used. If there is a great detail of line dust present, the respective control valves of the embodiments illustrated in Figs. l through 6 and 8 through l5 may be opened, or the valve 176 of Fig.4 7 closed, more or less, so as to permit a greater pressure drop through the bag before the controls operate. Likewise, if the voltage is higher than normal, these valves may be adjusted in the same manner so as to permit a greater pressure drop through the bag, and if these conditions change from time to time the user may readily adjust the valves so as to obtain the desired operation of the cleaner.

While the different forms of valves illustrated in Figs. 8 through l5 have been shown so connected as to regulate the bleeding of atmospheric air into the diaphragm chamber 70, in a manner similar to the valve 78 shown in Fig. 5, obviously they could be connected so as to control the bleeding of air into chamber 72, as does the valve 176 in Fig. 7.

While we have shown several more or less specic embodiments of our invention it will be understood that this has been done for purposes of illustration only and the scope of our invention is not to be limited thereby, but is to be determined from the appended claims.

What we claim is:

1. In combination with a vacuum cleaner having a casing enclosing a dust separating member and suction producing means for causing flow of air therethrough, a pneumatically actuated element for controlling the opera. tion of said cleaner, a housing, a diaphragm dividing said 1() housing into two chambers, conduit means for connecting the respective chambers to points in said casing on opposite sides of said dust separating member, valve means operable by a predetermined movement of said diaphragm for controlling ow of air between said suction producing means and said element, and a manually operable valve for regulating ow of air between one of said chambers and a region in which there exists a pressure different from the pressure in said one chamber.

2. In combination with a vacuum cleaner having a casing enclosing a dust separating member and suction producting means for causing ow of air therethrough, a pneumatically actuated element for controlling the operation of said cleaner, a housing, a diaphragm dividing said housing into two chambers, conduit means for connecting the respective chambers to points in said casing on opposite sides of said dust separating member, valve means operable by a predetermined movement of said diaphragm for controlling flow of air between said suc-l tion producing means and said element, and a manually operable valve for regulating the bleeding of atmospheric air into one of said chambers.

3. In combination with a vacuum cleaner having a casing enclosing a dust separating member and suction producing means for causing flow of air therethrough, a pneumatically actuated element for controlling the operation of said cleaner, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber to a point in said casing ahead of said dust separating member, conduit means connecting said high suction chamber to a point in said casing between said dust separating member and said suction producing means, valve means operable by a predetermined movement of said diaphragm for controlling ow of air be tween said suction producing means and said element, and a manually operable valve for regulating ow of atmospheric air into said high suction chamber.

4. In combination with a vacuum cleaner having-a casing enclosing a dust separating member and suction producing means for causing ow of air therethrough, a pneumatically actuated element of controlling the opera tion of said cleaner, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber to a point in said casing ahead of said Vdust separating member, conduit means connecting said high suction chamber to a point in said casing between said dust separating member and said suction producing means, valve means operable by a predetermined movement of said diaphragm for controlling flow of air between said suction producing means and said element, and a manually operable valve for regulating flow of atmospheric air into said low suction chamber.

5. In combination With a vacuum cleaner having a casing enclosing a dust separating member and suction producing means for causing ow of air therethrough, a pneumatically actuated element for controlling the operation of said cleaner, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber to a point in said casing ahead of said dust separating member, conduit means connecting said high suction chamber to a point in said casing between said dust separating member and said suction producing means, valve means operable bya predetermined movement of said diaphragm for controlling ow of air between said suction producing means and said element, conduit means connecting said low suction chamber with a point in said casing between said dust separating member and said suction producing means, and a manual operable valve for regulating ow of air through the last mentioned conduit means.

6. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing flow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said fiow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, conduit means connecting one of said suction chambers with atmosphere, and manually operable valve means for regulating fiow through the last mentioned conduit means con"- prising relatively movable members, one of said members being provided with a fixed orifice and the other of said members being provided with a plurality of fixed orifices of graduated sizes arranged so that relative movement of said members brings successive graduated orifices into registration with the first mentioned fixed orifice.

7. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing fiow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said flow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, conduit means connecting one of said suction chambers with atmosphere, and manually operable valve means for regulating fiow through the last mentioned conduit means comprising relatively rotatable members, one of' said members being provided with one fixed orifice and the other of said members being provided with a plurality of fixed orifices of graduated sizes arranged in a circle so that relative rotation of said members brings successive graduated orifices into registration with the first mentioned fixed orifice, and means for retaining said members in adjusted position with said one fixed orifice in registration with any selected one of said plurality of fixed orifices.

8. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing flow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between saidv dust separating means and said fiow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, conduit means connecting one of said suction chambers with atmosphere, and manually operable valve means for regulating ow through the last mentioned conduit means comprising relatively rotatable members, one of said members being provided with one fixed orifice and the other of said members being provided with a plurality of fixed orifices of graduated sizes arranged in a circle so that relative rotation of said members brings successive graduated orifices into registration with the first mentioned fixed orifice, and resilient means for yieldably retaining said members in adjusted position with saidone fixed orifice in registration with any selected one of said plurality of fixed orifices.

9. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing flow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said flow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, conduit means connecting one of said suction chambers with atmosphere, and manually operable valve means for regulating fiow through the last mentioned conduit means comprising a cylindrical member formed with a wall normal to its axis, said wall being provided with a plurality of xed orifices of graduated sizes arranged in a circle about said axis, a valve member rotatably mounted in said cylindrical member and having a face portion in rotational sliding contact with said wall, said face portion being provided with one fixed orifice at least as large as the largest of said plurality of fixed orices and disposed so that rotation of said valve member aligns said one fixed orifice with successive graduated orifices, and resilient means urging said face portion into sealing contact with said wall.

10. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing fiow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said fiow producing means, valve means actuted by a predetermined movement of said diaphragm for establishing communication between said element and said fiow producing means, a conduit connecting one of said suction chambers with atmosphere, a disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of fixed orifices of graduated sizes arranged in a circle, and means for rotating said disc for selectively bringing successive graduated orifices into registration with said end to thereby regulate flow through said conduit.

11. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing ow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said fiow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, a conduit connecting one of said suction chambers with atmosphere, a disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of fixed orifices of graduated sizes arranged in a circle, means for rotating said disc for selectively bringing successive graduated orifices into registration with said end to thereby regulate fiow through said conduit, and means for yieldably retaining said disc in adjusted position with any selected one of said graduated orifices in registration with said end.

12. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing ow of air therethrough, a pneumatically ac tuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said flow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said ow producing means, a conduit connecting one of said suction chambers with atmosphere, a disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of ixed orices of graduated sizes arranged in a circle, a resilient hollow cup member carried by the end of said conduit for making sealing contact with said disc, and means for rotating said disc for selectively bringing successive graduated orifices into registration with said cup member to thereby regulate flow through said conduit.

13. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing flow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing `said housing into a low suction chamber and a high suction chamber, conduit means connecting said low :suction chamber with a point in said casing ahead of .said dust separating means, conduit means connecting .said high suction chamber with a point in said casing between said dust separating means and said ow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, a conduit connecting one of said suction chambers with atmosphere, a disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of fixed orifices of graduated sizes arranged in a circle, a resilient hollow cup member carried by the end of said conduit for making sealing contact with said disc, means for displacing said disc away from said cup and for rotating said disc for selectively bringing successive graduated orifices into registration with said cup, and means for urging said disc into contact with said cup when any on'ce is in registration with said cup to thereby regulate ow through said conduit.

14. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing flow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said flow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said ow producing means, a conduit connecting one of said suction chambers with atmosphere, a disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of fixed orices of graduated sizes arranged in a circle, a resilient hollow cup member carried by the end of said conduit for making sealing contact with said disc, means for displacing said disc away from said cup and for rotating said disc for selectively bringing successive graduated orifices into registration with said cup, means for urging said disc into contact with said cup when any orifice is in registration with said cup to thereby regulate flow through said conduit, and means for preventing rotation of said disc when the latter is in contact with said cup.

15. In combination with a vacuum cleaner having a casing enclosing dust separating means and means for producing llow of air therethrough, a pneumatically actuated control element, a housing, a diaphragm dividing said housing into a low suction chamber and a high suction chamber, conduit means connecting said low suction chamber with a point in said casing ahead of said dust separating means, conduit means connecting said high suction chamber with a point in said casing between said dust separating means and said ow producing means, valve means actuated by a predetermined movement of said diaphragm for establishing communication between said element and said flow producing means, a conduit connecting one of said suction chambers with atmosphere, a resilient disc rotatably mounted adjacent to the end of said conduit, said disc being provided with a plurality of depressions arranged in a circle, a fixed orifice of different size extending through said disc from the bottom of each respective depression, and means for rotating said disc for bringing the end of said conduit into successive depressions to thereby selectively connect said conduit to xed orifices of different sizes for regulating flow through the conduit.

References Cited in the le of this patent UNITED STATES PATENTS 1,947,447 Brassert et al. Feb. 20, 1934 2,518,244 Moore Aug. 8, 1950 2,569,222 Beede et al. Sept. 25, 1951 2,641,330 Lofgren et al. June 9, 1953 

